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USING PYTHON In this homework, please implement the cipher described below. Plea

ID: 3882700 • Letter: U

Question

USING PYTHON


In this homework, please implement the cipher described below. Please provide the encryption and decryption function (source code) and show screenshots that prove its operation.

The 160-bit (20-byte) key that you will use

Key = "ndnsstwlmheotpsciwuo"

Please make sure that:

- Python program runs without errors and provides encryption and decryption functions

- Code has comments that explain main steps of the implementation

- Screenshots show tests with encryption and decryption


The user should be able to type in a work such as "engineering" then have it encrypt. Then display that new encrypted message, and ask for another input after its done.

Explanation / Answer

Encryption and decryption using AES algorithm

from crypto import random

from crypto.cipher import AES

import basse64

BLOCK_SIZE=32

def encrypt(message,passphrase);

IV=random.new().read(BLOCK_SIZE)

aes=AES.new(passphrase,AES.MODE_CFB,IV)

return base64.b64encode(aes.encrypt(message))

def decrypt(encrypted,passphrase);

IV=random.new().read(BLOCK_SIZE)

aes=AES.new(passphrase,AES.MODE_CFB,IV)

return aes.decrypt(base64.b64decode(encrypted)).